(a) Field of the Invention
The present invention relates to a method and an apparatus for transmitting a sounding reference signal (SRS) which is an uplink signal, or a physical uplink control channel (PUCCH) and a physical uplink shared channel (PUSCH) being an uplink channel.
(b) Description of the Related Art
In an existing long term evolution (LTE) single carrier system, only one carrier is allocated to uplink and downlink of a terminal. Meanwhile, in a carrier aggregation (CA) system, a plurality of uplink carriers or a plurality of downlink carriers may be allocated to the terminal. In this case, the number of uplink carriers may be different from the number of downlink carriers. Further, linkage between the uplink carrier and the downlink carrier is indicated by a parameter ul-CarrierFreq included in system information (SIB2: System Information Block type 2) of a type 2.
The carrier allocated to the terminal may be divided into a primary cell or a secondary cell. The primary cell means a cell which is indicated as a cell firstly performing a radio resource control (RRC) connection establishment process with a base station by a terminal, or a target cell by a serving cell in a handover process to obtain new RRC connection.
The secondary cell means a cell which is additionally set to provide an additional radio resource to the terminal after RRC connection is established through a primary cell. In the carrier aggregation system, a base station manages a secondary cell by terminals according to a measurement report, or uplink or downlink traffic of the terminal. The secondary cell may be added or removed through RRC signaling. An activation or deactivation operation may be indicated through a medium access control (MAC) control element (CE) with respect to the secondary cell in which RRC connection is established.
Meanwhile, there is a need for a technology of controlling uplink power in the LTE carrier aggregation system.